2-Amino-4,5-dichlorobenzaldehyde: Properties & Lab Use Guide

2-Amino-4,5-dichlorobenzaldehyde is a bifunctional aromatic building block bearing both an electron-donating amino group and an aldehyde group on a dichlorinated benzene ring, making it a versatile intermediate in pharmaceutical and heterocyclic synthesis.

Chemical Name

2-Amino-4,5-dichlorobenzaldehyde

SKU / Catalog Number

A191345

Molecular Formula

C7H5Cl2NO

Molecular Weight

190.03 g/mol

Key Functional Groups

Primary aromatic amine (–NH2), aldehyde (–CHO), two ring chlorine substituents

Primary Application

Intermediate in heterocyclic and pharmaceutical synthesis

Storage Recommendation

Store in a cool, dry, well-ventilated place away from light and moisture

Chemical Identity and Structure

2-Amino-4,5-dichlorobenzaldehyde (CAS registry number should be confirmed; see review flags) belongs to the class of substituted benzaldehydes. Its molecular formula is C₇H₅Cl₂NO, giving a molecular weight of approximately 190.03 g/mol. The molecule features three distinct reactive sites: (1) a formyl group (–CHO) at the 1-position relative to the amino group, which is electrophilic and participates readily in condensation reactions; (2) a primary aromatic amine (–NH2) at the 2-position, which is nucleophilic and can undergo acylation, cyclization, and reductive amination; and (3) chlorine substituents at the 4- and 5-positions, which activate or deactivate specific ring positions toward electrophilic or nucleophilic aromatic substitution and provide handles for palladium-catalyzed cross-coupling reactions.

The interplay between the electron-donating amino group and the electron-withdrawing aldehyde and halogens creates an electronically polarized ring system that is particularly suited for the construction of condensed heterocyclic frameworks such as benzimidazoles, quinolines, and benzoxazoles.

Synthetic Applications

The bifunctional nature of 2-Amino-4,5-dichlorobenzaldehyde makes it a highly valuable building block in medicinal and synthetic chemistry. The following applications are well established at the textbook level:

• Benzimidazole synthesis: The ortho amino–aldehyde motif is a classic precursor to benzimidazoles. Condensation with 1,2-diamines under oxidative or reductive conditions yields 2-substituted benzimidazoles bearing chlorine substituents at defined positions, which can be further diversified by cross-coupling.
• Schiff base formation: The aldehyde reacts with primary amines to form imines (Schiff bases), which serve as ligands in coordination chemistry or as intermediates for further cyclization.
• Quinoline and isoquinoline synthesis: Under Doebner–Miller or Skraup-type conditions, the aldehyde can contribute to ring-forming sequences that produce chlorinated quinoline derivatives useful in medicinal chemistry.
• Palladium-catalyzed cross-coupling: The aryl chloride bonds (C–Cl at the 4- and 5-positions) can participate in Suzuki–Miyaura, Buchwald–Hartwig, or Sonogashira coupling reactions, enabling rapid diversification of the molecular scaffold.
• Reductive amination: The aldehyde can be used in reductive amination protocols to introduce diversity at the benzylic nitrogen position.

Researchers in drug discovery use such dichlorinated aminobenzaldehyde intermediates to install halogen atoms at defined positions for structure–activity relationship (SAR) studies, leveraging the distinct electronic and steric effects of chlorine.

Handling, Safety, and Storage Guidelines

As with all aromatic amine and aldehyde-containing compounds, appropriate laboratory precautions are essential when working with 2-Amino-4,5-dichlorobenzaldehyde. The following guidelines reflect standard laboratory practice for this class of compound:

• Personal protective equipment (PPE): Wear chemical-resistant gloves (nitrile recommended), a laboratory coat, and safety goggles or a face shield at all times during handling. Use additional respiratory protection if working outside a fume hood.
• Engineering controls: All weighing, dissolution, and reaction steps involving this compound should be performed inside a well-functioning chemical fume hood to minimize inhalation exposure to dust and vapors.
• Skin and eye contact: In case of skin contact, wash the affected area immediately with soap and copious water for at least 15 minutes. For eye contact, irrigate immediately with water for at least 15 minutes and seek medical advice. The aromatic amine functionality may present sensitization risk; consult the current Safety Data Sheet (SDS) for full hazard classification.
• Storage: Store in a tightly sealed container in a cool (2–8 °C recommended for long-term stability; confirm with SDS), dry, and well-ventilated area away from direct light, moisture, oxidizing agents, and strong acids or bases.
• Waste disposal: Dispose of residues and contaminated materials in accordance with local, national, and institutional regulations for halogenated organic waste. Do not pour into drains.

Always consult the current Aladdin Scientific Safety Data Sheet (SDS) for SKU A191345 before use, as regulatory classifications and specific hazard data supersede the general guidance provided here.

Quality, Purity, and Ordering Information

Aladdin Scientific supplies 2-Amino-4,5-dichlorobenzaldehyde under catalog number A191345. When evaluating this reagent for your research, consider the following quality parameters:

• Purity specification: The purity grade and specification for SKU A191345 should be confirmed on the current product page or certificate of analysis (CoA). Typical analytical characterization for this compound class includes HPLC purity, melting point, and NMR identity confirmation.
• Certificate of Analysis (CoA): A lot-specific CoA is available on request or via the Aladdin Scientific website. The CoA documents the analytical results for each production batch, ensuring that the material meets the stated specification before dispatch.
• Packaging: Available pack sizes are listed on the product page. Contact Aladdin Scientific for bulk or custom quantities.
• Recommended applications: Suitable for research-grade synthetic chemistry and drug discovery applications. Not intended for clinical, diagnostic, or human/veterinary therapeutic use.

For procurement teams: this product is subject to standard Aladdin Scientific terms regarding payment, pricing, shipping, and returns. Please refer to the Aladdin Scientific website or contact your regional sales representative for current lead times and pricing.

Frequently asked questions

What is 2-Amino-4,5-dichlorobenzaldehyde used for in synthetic chemistry?

2-Amino-4,5-dichlorobenzaldehyde is primarily used as a bifunctional building block for the synthesis of heterocyclic compounds, including benzimidazoles, quinolines, and Schiff bases. The concurrent presence of a reactive aldehyde and a primary amine on the aromatic ring allows multiple cyclization and condensation strategies. The aryl chloride groups also enable palladium-catalyzed cross-coupling reactions for scaffold diversification.

How should 2-Amino-4,5-dichlorobenzaldehyde be stored to maintain stability?

This compound should be stored in a tightly sealed container under cool, dry, and dark conditions. Long-term storage at 2–8 °C is generally recommended for aldehyde and aromatic amine-containing compounds of this class to prevent oxidation and condensation side reactions; however, users should confirm the recommended storage conditions from the current Aladdin Scientific CoA or SDS for SKU A191345. Protect from moisture and incompatible materials such as strong oxidizers and strong acids.

Is 2-Amino-4,5-dichlorobenzaldehyde (A191345) suitable for GMP or clinical use?

No. SKU A191345 is supplied as a research-grade reagent intended solely for laboratory research and development purposes. It is not manufactured under GMP conditions and is not approved or intended for use in clinical diagnostics, pharmaceutical manufacturing for human or veterinary use, or any therapeutic application. Researchers requiring GMP-grade material should contact Aladdin Scientific for further guidance.

What solvents are commonly used to dissolve 2-Amino-4,5-dichlorobenzaldehyde?

Aromatic aldehydes and amino-substituted benzaldehydes of this type are generally soluble in common organic solvents such as dimethyl sulfoxide (DMSO), N,N-dimethylformamide (DMF), ethanol, methanol, acetonitrile, and ethyl acetate. Solubility in water is expected to be low due to the hydrophobic dichlorophenyl moiety. Users should verify solubility experimentally for their specific application conditions and concentrations.

References

1. March, J. Advanced Organic Chemistry: Reactions, Mechanisms, and Structure. 4th ed. Wiley-Interscience, 1992. (General reference for condensation and heterocycle-forming reactions of ortho-amino aldehydes.)
2. Clayden, J.; Greeves, N.; Warren, S. Organic Chemistry. 2nd ed. Oxford University Press, 2012. (Textbook-level reference for Schiff base formation, reductive amination, and aromatic substitution.
3. Aladdin Scientific product page for 2-Amino-4,5-dichlorobenzaldehyde, SKU A191345. https://www.aladdin-e.com (accessed 2024).

Products are supplied for research and development use only. Not for use in humans, animals, diagnosis, or therapy.